Apparatus and Method for Aerosol Collection and Fluid Analysis

ABSTRACT

An apparatus for aerosol collection and fluid analysis includes a rotary motor, an aerosol-collection disk configured for mounting on the rotary motor, and a fluid-analysis disk that is also configured for mounting on the rotary motor. The aerosol-collection disk includes at least one interior inlet, at least one peripheral outlet and a passage coupling the interior inlet with the peripheral outlet, and a particle collector opposite the peripheral outlet. The fluid-analysis disk includes at least one fluid in each of a first reservoir and in a second reservoir on or in the fluid-analysis disk and offset from a central axis of the disk, wherein each reservoir has an outlet and a stopper in the outlet of each reservoir to seal the reservoirs; and release of the fluids from the reservoirs is spin-induced.

GOVERNMENT SUPPORT

The invention was supported, in whole or in part, by GrantFA8721-05-C-0002 from the Director of Defense Research and Engineering.The Government has certain rights in the invention.

BACKGROUND

A variety of contexts exists wherein air sampling and analysis ofparticulates or organisms suspended therein is desirable. Exemplaryapplications where air sampling and analysis can serve to protect humanhealth include detection of pathogens in air supplies and air-qualitymonitoring in, e.g., office buildings, public venues, factories, minesand ships.

SUMMARY

Apparatus and methods for aerosol collection and fluid analysis aredescribed herein. Various embodiments of the apparatus and methods mayinclude some or all of the elements, features and steps described below.

An apparatus for aerosol collection and fluid analysis includes a rotarymotor, an aerosol-collection disk configured for mounting on a rotarystage of the motor, and a fluid-analysis disk that is also configuredfor mounting on the rotary motor. The aerosol-collection disk includesat least one interior inlet, at least one peripheral outlet and at leastone passage coupling the interior inlet with the peripheral outlet, anda particle collector opposite the peripheral outlet. The fluid-analysisdisk includes at least one fluid in each of a first reservoir and asecond reservoir on or in the fluid-analysis disk and offset from acentral axis of the disk, wherein each reservoir has an outlet and astopper in the outlet of each reservoir to seal the reservoirs; andrelease of the fluids from the reservoirs via centrifugal force isspin-induced by the rotary motor.

The fluid-analysis disk can be of any of the following designs. In afirst embodiment, the outlet of the first reservoir faces a firstdirection relative to the central axis; and the outlet of the secondreservoir faces a second direction (distinct from the first direction)relative to the central axis. In a second embodiment, the firstreservoir is offset from the central axis of the disk by a first radius;and the second reservoir is offset from the central axis of the disk bya second shorter radius. In a third embodiment, the first stopper in thefirst reservoir has a first release or sealing force; and the secondstopper in the second reservoir has a second release or sealing force,wherein the first release or sealing force is less than the secondrelease or sealing force.

Embodiments of the apparatus and methods can provide air-qualitymonitoring with the following advantages over conventional air-qualitymonitoring systems that use vacuum or blower systems for aerosolcollection: simple design and operation; high efficiency; reducedcooling; low weight and volume; high portability; low expense for theapparatus and its operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts radial flow through a spinning aerosol-collection disk.

FIG. 2 shows an aerosol-collection disk spun by a motor with aparticle-laden air flow entering inlets at the center of theaerosol-collection disk, exiting the disk at its perimeter and impingingon the inner surface of an annular ring co-rotating with theaerosol-collection disk.

FIG. 3 is a sectional illustration of a prototype model of theaerosol-collection disk as depicted in FIG. 2.

FIG. 4 depicts acceleration of a point on a fluid-dispensing diskrotating with constant angular velocity.

FIG. 5 shows a plunger sealing a reservoir on a fluid-dispensing disk.

FIG. 6 depicts the plunger removed from the gate of FIG. 5 to allowfluid to dispense.

FIG. 7 illustrates multiple reservoirs at different radii on afluid-dispensing disk for sequential dispensing of fluids usingmechanical valves.

FIG. 8 shows a gate with a plunger in a “normally open” configuration ona fluid-dispensing disk.

FIG. 9 depicts the gate of the “normally open” configuration in a closedposition.

FIG. 10 shows a viscous plug subjected to constant angular velocity on afluid dispensing disk.

FIG. 11 illustrates multiple reservoirs with viscous plugs at differentradii on a fluid-dispensing disk for sequential dispensing of fluids.

FIG. 12 depicts the acceleration components of a point on a rotatingfluid-dispensing disk due to a disk having some prescribed angularvelocity and angular acceleration.

FIG. 13 provides a series of plots of vector angle, φ as shown in FIG.12 versus time for different combinations of (a) initial angularvelocity and (b) angular acceleration.

FIG. 14 depicts a reservoir oriented on a fluid-dispensing disk with agate and plunger sealing the reservoir at angle ψ from the radius of thereservoir.

FIG. 15 shows a plunger subjected to vectored acceleration on afluid-dispensing disk allowing the fluid in the reservoir to dispense.

FIG. 16 depicts multiple reservoirs sealed with plungers oriented atdifferent angles on a fluid-dispensing disk for spin-vectored dispensingof a fluid.

FIG. 17 depicts spin vectoring to dispense fluid from one of thereservoirs shown in FIG. 16.

FIG. 18 illustrates another embodiment of multiple reservoirs withplungers on a fluid-dispensing disk for spin vectoring.

FIG. 19 shows a “normally open” gate configuration for use with spinvectoring.

FIG. 20 shows the “normally open” gate configuration of FIG. 19 inclosed position.

FIG. 21 depicts a reservoir oriented on a fluid-dispensing disk with agate and viscous plug at angle ψ from the radius of the reservoir.

FIG. 22 shows a viscous plug subjected to vectored acceleration on afluid-dispensing disk.

FIG. 23 depicts multiple reservoirs with viscous plugs oriented atdifferent angles on a fluid-dispensing disk for spin-vectored dispensingof a fluid.

FIG. 24 shows a combination of two vectored reservoir-plugconfigurations with a non-vectored reservoir-plug configuration.

FIG. 25 illustrates another embodiment of multiple reservoirs withviscous plugs on a fluid-dispensing disk for spin vectoring.

In the accompanying drawings, like reference characters refer to thesame or similar parts throughout the different views; and apostrophesare used to differentiate multiple instances of the same or similaritems sharing the same reference numeral. The drawings are notnecessarily to scale, emphasis instead being placed upon illustratingparticular principles, discussed below.

DETAILED DESCRIPTION

The foregoing and other features and advantages of various aspects ofthe invention(s) will be apparent from the following, more-particulardescription of various concepts and specific embodiments within thebroader bounds of the invention(s). Various aspects of the subjectmatter introduced above and discussed in greater detail below may beimplemented in any of numerous ways, as the subject matter is notlimited to any particular manner of implementation. Examples of specificimplementations and applications are provided primarily for illustrativepurposes.

Unless otherwise defined, used or characterized herein, terms that areused herein (including technical and scientific terms) are to beinterpreted as having a meaning that is consistent with their acceptedmeaning in the context of the relevant art and are not to be interpretedin an idealized or overly formal sense unless expressly so definedherein. For example, if a particular shape is referenced, the shape isintended to include imperfect variations from ideal shapes, e.g., due tomachining tolerances.

Although the terms, first, second, third, etc., may be used herein todescribe various elements, these elements are not to be limited by theseterms. These terms are simply used to distinguish one element fromanother. Thus, a first element, discussed below, could be termed asecond element without departing from the teachings of the exemplaryembodiments.

Spatially relative terms, such as “above,” “below,” “left,” “right,” “infront,” “behind,” and the like, may be used herein for ease ofdescription to describe the relationship of one element to anotherelement, as illustrated in the figures. It will be understood that thespatially relative terms, as well as the illustrated configurations, areintended to encompass different orientations of the apparatus in use oroperation in addition to the orientations described herein and depictedin the figures. For example, if the apparatus in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the exemplary term, “above,” may encompass both an orientation ofabove and below. The apparatus may be otherwise oriented (e.g., rotated90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

Further still, in this disclosure, when an element is referred to asbeing “on,” “connected to” or “coupled to” another element, it may bedirectly on, connected or coupled to the other element or interveningelements may be present unless otherwise specified.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of exemplary embodiments.As used herein, singular forms, such as “a” and “an,” are intended toinclude the plural forms as well, unless the context indicatesotherwise. Additionally, the terms, “includes,” “including,” “comprises”and “comprising,” specify the presence of the stated elements or stepsbut do not preclude the presence or addition of one or more otherelements or steps.

In methods for aerosol collection and fluid analysis, particulates froman aerosol sample can be collected using an aerosol-collection disk 12,as described in section A, below. The collected particulates can then beadded to a dispersing fluid and dispensed via spinning from afluid-dispensing disk 14, as described in section B, below, foranalysis.

Examples of air samples that can be taken for the aerosol-collectionstep include air samples that may contain harmful pathogens as well asair samples from, e.g., factories, mines and ships for air-qualityevaluation/monitoring. If an air sample containing a pathogen is taken,the pathogen can be collected in the aerosol-collection step and thenadded to the dispensing fluid 33 (e.g., a liquid). In thefluid-dispensing step, the fluid 33 containing the pathogen can beloaded into one of multiple reservoirs 32 in or on a fluid-dispensingdisk 14, multiple embodiments of which are described in section B,below. By governing the rotation of the fluid-dispensing disk 14, thepathogen-containing fluid 33 can be selective dispensed from itsreservoir 32 at one point in time and additional liquids can beselectively released from their respective reservoirs 32 at differenttimes.

In one embodiment, the pathogen is collected first from the aerosolcloud via the spin-induced aerosol collection method on the disk 14;then, in a pre-wash step, a fluid 33 (e.g., a CO2i cell culture medium,which is a common off-the-shelf reagent) is released to wash off anyprotective coatings on the pathogen (an optional step); next, a secondliquid (e.g., B-Cells suspended in the CO2i medium) is released tointeract with the pathogen (e.g., tag it with a detectable marker orcause it to luminesce); a third release of the same second liquid maythen be dispensed to perform a confirmation assay on the same sample ofparticles (optional step); a subsequent fourth delivery may be of adifferent strain of B-Cells engineered to detect another pathogen,allowing one collection of particles to be analyzed multiple times todetect various pathogens (optional step); and then a final, fifthdispense may be of a fluid, such as CO2i medium, to rinse the test areain preparation for the next particle collection and test sequence(optional step). Various combinations of the mentioned optional stepsmay be used depending on the test required including but not limited tomultiple confirmation assays, confirmation assays of multiple tests perpathogen collection, selective dispensing of the pre-wash dispense, etc.The fluids 33 can be released via vector acceleration of the rotatingliquid with different orientations of reservoirs 32 and releasemechanisms or via differences in the radii of the reservoirs 32 on or inthe fluid-dispensing disk 14, as discussed in section B.

Both the aerosol-collection disk 12 and the fluid-dispensing disk 14 areconfigured for mounting on a stage including a shaft 18 on a rotarymotor 16 via a motor mount, such as a common motor coupling, on theshaft 18. The disks can have a diameter between about 2 inches to about18 inches (e.g., about 4-5 inches) and a thickness, e.g., of one inch orless (e.g. about ¼″ thick) The motor 16, (e.g., a 10.5 Watt Model2842024C DC motor from FAULHABER Group, Germany) is provided with acontrol for varying speed of rotation and acceleration of the stage,allowing for controlled rotational velocity and acceleration of the disk12/14, as described below. In alternative embodiments,aerosol-collection and fluid dispensing are incorporated into a singledisk, with the structures for both functions incorporated into/onto asingle platform.

A. Spin-Induced Aerosol Collection:

An aerosol-collection disk 12 having a hole in the center (i.e., theinlet 22), and channels 24 running radially outward to outlets 26 at theouter diameter of the aerosol-collection disk 12 is shown in FIGS. 1 and2. When spun at an angular velocity, ω, a radial flow, V, of an aerosolresults due to the generated tangential flows, V_(i) at the inlet 22 andV_(e) at the exhaust or outlet 26. This flow can be generated entirelyor almost entirely by centrifugal acceleration. The radial distance tothe inlet 22 and the outlet 26 is R_(i) and R_(e), respectively.

The required radial flow velocity, V, may be calculated from the desiredvolume flow rate, Q, and the cross-sectional area, A, of the port, asfollows:

V=Q/A,   (1)

and the resulting pressure drop, Δp, across the radial channel 24between the inlet 22 and the outlet 26 is expressed, as follows:

Δp=p _(i) −p _(e)=1/2ρV ²,   (2)

wherein p_(i) is the pressure of the aerosol at the inlet 22, and p_(e)is the pressure of the aerosol at the outlet 26. Variable, p, is airdensity. By Bernoulli's equation, the pressures and tangentialvelocities at the inlet 22 and outlet 26 are related, as follows:

p _(i)+1/2ρV _(i) ² =p _(e)+1/2ρV _(e) ²,   (3)

and the tangential flows are expressed as follows:

V_(i)=ωR_(i) and V_(e)=ωR_(e).   (4)

Substituting Equation 1, Equation 2 and Equation 4 into Equation 3 andrearranging allows the determination of the required disk angularvelocity, as follows:

$\begin{matrix}{\omega = {\left( \frac{2\Delta \; p}{\left( {R_{e}^{2} - R_{i}^{2}} \right)\rho} \right)^{1/2}.}} & (5)\end{matrix}$

FIG. 2 further depicts the aerosol-collection disk 12 spun by a motor16, with the particle-laden air flow entering the inlets 22 at thecenter of the disk 12. Upon exiting the aerosol-collection disk 12, theairflow makes a sudden turn, resulting in the particles 30 in the flowimpinging on the inner surface of an annular-band particle collector 28co-rotating with the disk 12. The annular band 28 can be in the form ofa continuous ring or in the form of one or more segments of a ring,where at least one segment is in the vicinity of each outlet port 26.

A sectional view of a computer-aided-design model of a prototype used toquantify the aerosol-collection disk 12 is shown in FIG. 3, with aerosolflow shown with the arrows. Particles 30 from the aerosol are depositedon the inner surface of the annular-ring particle collector 28, which isconnected to the spinning aerosol-collection disk 12 as the air flowmakes the sharp turn to exhaust.

For an aerosol-collection disk 12 having a 0.5-inch radius to the inletnozzle 22 and a 2-inch radius to the outlet port 26 with a 1-mmdiameter, the rotation speed (expressed in revolutions per minute), forthe disk 12 was computed for achieving three desired flow rates perchannel (ch) in liters per minute per channel and is show in Table 1.

TABLE 1 Flow Rate Disk Speed  4 l/min/ch  2,900 RPM 19 l/min/ch 13,900RPM 30 l/min/ch 22,800 RPM

The lower bound of the efficiency of the spin-induced-aerosol-collectionconcept, relative to using a conventional blower capable of achievingsimilar volume flow rates, was computed based on the power of the totalflow through the prototype aerosol-collection disk 12, P_(flow), therated motor maximum power, P_(motor), and the published motorefficiency, η_(motor), using the following equations:

$\begin{matrix}{{P_{flow} = {\left( {{\Delta \; p} + {\frac{1}{2}\rho \; V^{2}}} \right){\sum\limits_{n}v_{n}}}},} & (6)\end{matrix}$

where n=1:N_(p), and N_(p) is the number of ports. v_(n) is the volumeflow rate through each port. The minimum bound of the efficiency of thespin-induced aerosol collection (SIAC), η_(SIAC), can be expressed asfollows:

$\begin{matrix}{\eta_{SIAC} = {\frac{P_{flow}}{P_{motor}}{\eta_{motor}.}}} & (7)\end{matrix}$

The efficiency of a conventional blower attaining similar flow rates wasdetermined by comparing measured air flow, measured using a flow meter,to the measured blower electrical power consumed. Table 2 shows that theSIAC efficiency lower bound of 51% is eight times greater than theexample blower efficiency of 6%.

TABLE 2 Electrical Total Flow Pressure Power Power Flow Rate Drop(Input) (Output) Efficiency SIAC  98 l/min 1390 Pa 8.86 W (1) 4.54W >51% (2) Blower 100 l/min 1400 Pa 40.3 W     2.4 W  6% (3)As indicated, above:

-   -   (1) the SIAC electrical power was the maximum motor power/motor        efficiency, 6.56 W/0.74=8.86 W;    -   (2) the actual input power is unknown and thus efficiency may be        higher than 51%; and    -   (3) the best measured blower efficiency was 14%.

Additional benefits of the SIAC concept over using a conventional blowerare reduced volume, reduced weight and less cooling due to higherefficiency.

B. Spin-Induced Fluid Dispensing

i) Sequential Constant-Velocity Dispensing of Fluids

A point on a fluid-dispensing disk 14 at radius, r, with constantangular velocity, ω, sees a radially outward acceleration, a_(n)=rω, asshown in FIG. 4.

Considering the point on the disk 14 to be the location of a plunger 34,the plunger 34, which is loaded by a spring 38, may be used to seal areservoir 32 containing fluid 33, as shown in FIG. 5. The force due tonormal acceleration of the plunger 34 is simply the mass of the plunger34, m_(p), times a_(n) or f_(p)=m_(p)a_(n)=m_(p)(rω). When the netforce, f_(n), acting on the plunger 34 is greater than and in theopposite direction to the net force due to the spring 38 and otherresistive forces, such as stiction (static friction), mechanical detent,and inertia, the spring 38 compresses and the plunger 34 moves radiallyoutward, opening the outlet gate 42 and allowing the fluid to dispense44, as shown in FIG. 6. In other embodiments, the plunger 34 can be heldin the outlet gate 42 not by a spring 38 but instead by anothermechanism, such as a detent or a strip of breakable material, such astape, that will rip away at a prescribed angular velocity or forcevector.

FIG. 7 shows a fluid-dispensing disk 14 with three reservoirs 32, eachat different distances from the spin center (e.g., with a differencebeyond normal machining tolerances, such as a difference in radius of atleast 5% or 10% between each reservoir). For the case shown, eachreservoir 32 is sealed using identical plungers 34 and spring stiffnesssuch that the force required to open each is similar. The plungers 34for each reservoir 32 are located at radii, r₁, r₂, and r₃, wherer₁>r₂>r₃, as shown. For a given angular velocity, ω, the normalacceleration at each of the three plungers 34 is a_(n1)>a_(n2)>a_(n),thus the forces due to normal acceleration acting on the plungers 34 arethen f₁>f₂>f₃, having respective net forces, after subtracting out theforces resisting plunger motion, of f_(1,net)>f_(2,net)>f_(3,net).

At the critical angular velocity, ω₁, the net force f_(1,net) acting onthe plunger 34′ sealing the first reservoir 32′ is greater than theresting force due to the stiffness of the spring 38 and other resistiveforces, such as stiction, of the plunger 34, resulting in the plunger34′ moving radially outward, dispensing the fluid 33 from the reservoir32′. Since the critical angular velocities of the remaining reservoirs32″ and 32′″ are greater than ω₁ (i.e., ω₃>ω₂>ω₁), and the plungers 34″and 34′″ at the second and third reservoirs 32″ and 32′″ remain intact,sealing their respective reservoirs 32. Increasing the angular velocityto ω₂, the plunger 34″ moves radially outward, dispensing fluid 33 fromthe second reservoir 32″ while keeping the plunger 34′″ sealing thethird reservoir 32′″ intact. Further increasing the angular velocity toω₃ results in the remaining third plunger 34′″ moving radially outward,dispensing the fluid 33 from the third reservoir 32′″.

This concept may also be used to stop a fluid from flowing. As shown inFIG. 8, the plunger 34 is designed in a “normally open” configuration,allowing fluid 33 to flow through the gate 42 for angular velocitiesless than the critical velocity, ω₁. The fluid 33 may originate in areservoir 32 located in or on the fluid-dispensing disk 14, as shown, ormay originate outside the disk 14 and be passing through it via aflow-through channel.

As ω→ω₁, the net force acting on the plunger 34, f_(net), is greaterthan the sum of resistive forces inhibiting plunger motion allowing theplunger 34 to move and seal the gate 42, thus preventing further flow ofthe fluid 33, as shown in FIG. 9.

Without the benefit of a mechanical latch securing the plunger 34 in theclosed position, the fluid 33 may be allowed to flow by decreasing theangular velocity, ω, to below the critical angular velocity. However,the use of a mechanical latch securing the plunger 34 may be used toprevent flow from recurring after slowing from the critical angularvelocity.

In other embodiments, a viscous plug 36 is used in place of the plunger34, wherein the viscous plug 36 is used to seal a reservoir 32containing fluid 33, as shown in FIG. 10. The viscous plug 36, uponachieving a minimum angular velocity, is ejected due to the resultingnormal acceleration, a_(n), acting on it such that the shear forceacting on the viscous plug at the wall is overcome by the body forceacting on the viscous plug. The normal acceleration, a_(n), required todispense the viscous plug is expressed as follows:

$\begin{matrix}{{a_{n} \geq \frac{2{\tau_{w}\left( {w + h} \right)}}{\rho \; {wh}}},} & (8)\end{matrix}$

where τ_(w) is the shear force of the viscous plug, having density ρ,acting at the wall of the duct of width, w and height, h.

A fluid-dispensing disk 14 with three reservoirs 32, each at differentdistances from the spin center is shown in FIG. 11. The viscous plugs 36for each reservoir 32 are located at radii, r₁, r₂, and r₃, wherer₁>r₂>r₃, as shown. For a given angular velocity, ω (i.e.,a_(n1)>a_(n2)>a_(n3)); thus, the forces due to normal accelerationacting on the viscous plugs 36 are then f₁>f₂>f₃. At the criticalangular velocity, ω₁, the net force, f₁, acting on the viscous plug 36′sealing the first reservoir 32′ is sufficiently large to overcome anyresistive forces keeping the viscous plug 36′ in place; and, thus, theviscous plug 36′ is ejected from the gate, dispensing the fluid 33 fromthe first reservoir 32′. Since the critical angular velocities of theremaining reservoirs 32″ and 32′″ are greater than ω₁, ω₃>ω₂>ω₁, theviscous plugs 36″ and 36′″ at the second and third reservoirs 32″ and32′″ remain intact. Increasing the angular velocity to ω₂ ejects theviscous plug 36″ and fluid 33 from the second reservoir 32″ whilekeeping the viscous plug 36′″ sealing the third reservoir 32′″ intact.Further increasing the angular velocity to ω₃ ejects the remaining thirdviscous plug 36′″, dispensing the fluid 33 from the third reservoir32′″.

ii) Spin-Vectored Dispensing of Fluids

A point on a fluid-dispensing disk 14 at a radius, r, having an initialangular velocity, ω₀, and angular acceleration, α, is subject to theacceleration vectors shown in FIG. 12, where the normal acceleration,a_(n), can be expressed as follows:

{right arrow over (a)} _(n) ={right arrow over (r)}(ω₀ +αt)² {rightarrow over (e)} _(n),   (9)

where t is time, and e_(n) is the unit vector describing the directionof the radial or normal acceleration; and the tangential acceleration,a_(t), can be expressed as follows:

{right arrow over (a)}_(t)={right arrow over (r)}α{right arrow over(e)}_(t)   (10)

where e_(t) is the unit vector describing the direction of thetangential acceleration having an acceleration magnitude,

|a|=√{square root over ((a _(n) ² +a _(t) ²))},   (11)

and an acceleration vector angle,

$\begin{matrix}{\varphi = {{\tan^{- 1}\left( \frac{a}{\left( {\omega_{0} + a} \right)^{2}} \right)}.}} & (12)\end{matrix}$

FIG. 13 shows variation in vector angle over time, φ(t), due toincreasing angular velocity, ω, of the disk 14 due to constant angularacceleration, α, for an ideal (instant on) motor 16 starting from threedifferent initial angular velocities ω₀ (0 RPM, 20 RPM, and 200 RPM).All accelerations shown are positive and begin at t=0.5 seconds.Acceleration due to an actual motor 16 will have a ramp-up ofacceleration, thereby resulting in an initial increasing vector angle,φ. For continuing acceleration, the vector angle, φ, approaches thenormal (φ→0) as per equation 12 for increasing time as the angularvelocity (see equation 9, αt) increases.

The vector angle, φ, depends on (a) initial spin rate, ω₀; (b) angularacceleration, α; and (c) duration of the applied angular acceleration,t. For the curves shown in FIG. 13, solid lines show the vector angle,φ, versus time, t, starting with the motor 16 at zero initial angularvelocity, ω₀=0 RPM. Dashed lines have ω₀=20 RPM and dot-dash lines arefor ω₀=200 RPM. The largest vector angles, φ, are for large angularacceleration, α, with an initial angular velocity, ω₀=0.

The fluid-dispensing disk 14 in this embodiment takes advantage of theability to vector the net acceleration acting at a point on theaccelerating disk 14 by pulsing the angular velocity of the disk 14. Thepoint on the disk 14 where we consider the vectored acceleration is thelocation of a plunger 34 loaded by a spring 38 anchored to the disk 14,wherein the plunger 34 acts as a stopper to seal a reservoir 32containing fluid 33; the plunger 34 may be located at the end of aflow-through channel extending from the reservoir 32 at the gate 42 of arunner 40 and oriented at an angle, ψ, to the radius, as shown in FIG.14, or the reservoir can be in the form of a flow-through channelthrough which the fluid is supplied.

Applying angular acceleration, α, to the fluid-dispensing disk 14, theacceleration acting on the plunger 34 may be vectored to some angle, φ.The force due to acceleration of the plunger 34 is simply the mass ofthe plunger 34 times the acceleration magnitude, a, or f_(p)=m_(p)a.Orienting the acceleration vector such that φ→ψ, as shown in FIG. 15,aligns the force vector, f_(net), to coincide with the angle along whichthe runner is aligned, compressing the spring 38 to displace the plunger34 from the gate 42 to break the seal to the reservoir 32, allowing thefluid 33 to dispense there from, as shown by arrow 44.

A fluid-dispensing disk 14 with two reservoirs 32 is shown in FIG. 16.Each reservoir 32 has the same design but is oriented with its gate 42at a different angle, ψ₁, ψ₂, to the radius, r (e.g., with theorientation angle differing by at least 5° or 10°). For this example,the plunger 34 for each reservoir 32 is at the same radial distance, r,from the center. Applying angular acceleration, α₁, to the disk 14 suchthat φ₁→ψ₁ compresses the spring 38′ to displace the plunger 34′ andconsequently dispenses the corresponding fluid 33 from the firstreservoir 32′ in the form of an exiting flow 44, as shown in FIG. 17,while keeping the second reservoir 32″ sealed and its fluid 33 containedand intact. Fluid 33 in the second reservoir 32″ may then be dispensedby applying α₂, such that φ₂→ψ₂, thereby compressing spring 38″ andretracting plunger 34″.

This process may be repeated for multiple reservoirs 32 having differentgate/runner angles, ψ_(l), as shown in FIG. 18, where multiplereservoirs 32 having similar geometries and gate/runner orientation maybe combined, as shown. Here, several reservoirs 32 may be dispensedsimultaneously, while the remaining reservoirs 32 remain intact. Forexample, three pairs of reservoirs 32 are shown having three differentrunner angles, ψ₁, ψ₂ and ψ₀, (the angle of each respective pairdiffering, e.g., by at least 10° from the other pairs) where the pair ofψ₀ reservoirs 32′ are oriented in line with the radius allowing fordispensing of both simultaneously using the constant-angular-velocitymethod. Each remaining reservoir pair 32″ and 32′″ with ψ₁ and ψ₂,respectively, may be dispensed simultaneously using spin vectoring.

In addition to gate/runner angles, tailoring of the dispensingconditions may be achieved by also changing the radial distance of theplunger 34, the viscosity of the viscous plug 36 (in the case of aviscous plug) and/or the geometry of the gate holding the plunger 34.Various combinations of gate/runner angles, radii, spring stiffness,plunger mass, friction, etc., may be used to achieve the desireddispensing characteristics of the fluid-dispensing disk 14.

In these embodiments, the process is shown for fluids originating in thespinning fluid-dispensing disk 14; however, the method may also be usedto regulate fluid flow through the fluid-dispensing disk 14 given fluidsoriginating outside of it and fed through a flow-through channel in thefluid-dispensing disk 14.

This concept may also be used to stop a fluid from flowing. As shown inFIG. 19, the plunger 34 is designed in a “normally open” configuration,allowing fluid 33 to flow through the gate 42. Upon reaching a criticallinear acceleration acting on the plunger 34 via spin vectoring, theplunger 34 moves outward sealing the gate 42 and restricting the flow offluid 33, as shown in FIG. 20.

Without the benefit of a mechanical latch securing the plunger 34 in theclosed position, the fluid 33 may be allowed to flow by reducing theangular acceleration to below the critical angular acceleration.However, the use of a mechanical latch securing the plunger 34 may beused to prevent flow from recurring after reducing the angularacceleration below the critical angular acceleration.

In an alternative embodiment of the fluid-dispensing disk 14, theplunger 34 of the preceding embodiments is replaced with a viscous plug36 [e.g., formed of grease or petroleum jelly (such as VASELINEpetroleum jelly produced by Unilever)], as shown in FIG. 21. As in theabove-described embodiments that include a plunger 34, applying angularacceleration to the fluid-dispensing disk 14 vectors the accelerationacting on the viscous plug 36 to some angle, φ, where the force, f_(p),due to acceleration, a, of the viscous plug 36 is simply the mass,m_(p), of the viscous plug 36 times the acceleration magnitude, a, orf=m_(p)a. Orienting the acceleration vector such that φ→ψ, as shown inFIG. 22, aligns the force vector to the runner angle to allow theviscous plug 36 to flow, breaking the seal to the reservoir 32 andallowing the fluid 33 to dispense.

A fluid-dispensing disk 14 with two reservoirs 32 and viscous plugs 36is shown in FIG. 23. Each reservoir 32 has the same design but isoriented at a different angle, ψ₁, ψ₂, to the radius (e.g., differing byat least 5° or 10°). For this example, the viscous plug 36 for eachreservoir 32 is at the same radial distance from the center. Applyingangular acceleration, α₁, to the disk 14 such that φ₁→ψ₁ displaces thefirst viscous plug 36′ and dispenses the fluid 33 from the firstreservoir 32′ while keeping the second reservoir 32″ sealed. Fluid 33 inthe second reservoir 32″ may then be dispensed by applying α₂, such thatφ₂→ψ₂, thereby releasing the second viscous plug 36″. This process maybe repeated for multiple reservoirs 32 having different gate/runnerangles, ψ_(l).

FIG. 24 shows the same configuration as seen in FIG. 15 with anadditional reservoir 32′″ oriented at ψ=0°. For this configuration,depending on the gate/runner orientation, the ψ=0° reservoir 32′″ may bedispensed at constant angular velocity and the two remaining reservoirs32′ and 32″ may be dispensed by spin vectoring.

Multiple reservoirs 32 having similar geometries and gate/runnerorientation may be combined, as shown in FIG. 25. Here, severalreservoirs 32 may be dispensed simultaneously while the remainingreservoirs 32 remain intact.

In addition to gate/runner angles, tailoring of the dispense conditionsmay be achieved by also changing the radial distance of the viscous plug36, the viscosity of the viscous plug 36 and/or the geometry of the gateholding the viscous plug 36. Various combinations of gate/runner angles,radii, etc., may be used to achieve the desired dispensingcharacteristics of the disk 14.

In describing embodiments of the invention, specific terminology is usedfor the sake of clarity. For the purpose of description, specific termsare intended to at least include technical and functional equivalentsthat operate in a similar manner to accomplish a similar result.Additionally, in some instances where a particular embodiment of theinvention includes a plurality of system elements or method steps, thoseelements or steps may be replaced with a single element or step;likewise, a single element or step may be replaced with a plurality ofelements or steps that serve the same purpose. Further, where parametersfor various properties are specified herein for embodiments of theinvention, those parameters can be adjusted up or down by 1/100^(th),1/50^(th), 1/20^(th), 1/10^(th), ⅕^(th), ⅓^(rd), ½, ⅔^(rd), ¾^(th),⅘^(th), 9/10^(th), 19/20^(th), 49/50^(th), 99/100^(th), etc. (or up by afactor of 1, 2, 3, 4, 5, 6, 8, 10, 20, 50, 100, etc.), or by rounded-offapproximations thereof, unless otherwise specified. Moreover, while thisinvention has been shown and described with references to particularembodiments thereof, those skilled in the art will understand thatvarious substitutions and alterations in form and details may be madetherein without departing from the scope of the invention. Furtherstill, other aspects, functions and advantages are also within the scopeof the invention; and all embodiments of the invention need notnecessarily achieve all of the advantages or possess all of thecharacteristics described above. Additionally, steps, elements andfeatures discussed herein in connection with one embodiment can likewisebe used in conjunction with other embodiments. The contents ofreferences, including reference texts, journal articles, patents, patentapplications, etc., cited throughout the text are hereby incorporated byreference in their entirety; and appropriate components, steps, andcharacterizations from these references optionally may or may not beincluded in embodiments of this invention. Still further, the componentsand steps identified in the Background section are integral to thisdisclosure and can be used in conjunction with or substituted forcomponents and steps described elsewhere in the disclosure within thescope of the invention. In method claims, where stages are recited in aparticular order—with or without sequenced prefacing characters addedfor ease of reference—the stages are not to be interpreted as beingtemporally limited to the order in which they are recited unlessotherwise specified or implied by the terms and phrasing.

What is claimed is:
 1. An apparatus for aerosol collection and fluidanalysis, comprising: a rotary motor including a stage configured forrotation; an aerosol-collection disk including at least one interiorinlet, at least one peripheral outlet and a passage coupling theinterior inlet with the peripheral outlet, and a particle collectoropposite the peripheral outlet, wherein the collection disk isconfigured for mounting on the stage of the rotary motor for rotationthereon; a fluid-analysis disk configured for mounting on the stage ofthe rotary motor for rotation thereon, the fluid-analysis diskcomprising at least one fluid in each of a first reservoir and a secondreservoir on or in the fluid-analysis disk and offset from a centralaxis of the disk, wherein each reservoir has an outlet and a stopper inthe outlet of each reservoir to seal the reservoirs, and wherein thefluid-analysis disk is characterized by at least one of the following:a) the outlet of the first reservoir faces a first direction relative tothe central axis, and the outlet of the second reservoir faces a seconddirection relative to the central axis, wherein the second directiondiffers from the first direction; b) the first reservoir is offset fromthe central axis of the disk by a first radius, wherein the secondreservoir is offset from the central axis of the disk by a second radiusthat is less than the first radius; and c) the first stopper in thefirst reservoir has a first release or sealing force, and the secondstopper in the second reservoir has a second release or sealing force,wherein the first release or sealing force is less than the secondrelease or sealing force.
 2. The apparatus of claim 1, furthercomprising a particle collector mountable opposite the peripheral outletof the aerosol-collection disk.
 3. The apparatus of claim 2, wherein theparticle collector includes at least a segment of an annular band towhich particles can adhere upon contact.
 4. The apparatus of claim 1,wherein the outlet of the first reservoir faces the first directionrelative to the central axis, and the outlet of the second reservoirfaces the second direction relative to the central axis, wherein thesecond direction differs by at least 5° from the first direction.
 5. Theapparatus of claim 1, wherein the first reservoir is offset from thecentral axis of the disk by the first radius, and the second reservoiris offset from the central axis of the disk by the second radius, whichis at least 5% less than the first radius.
 6. The apparatus of claim 1,wherein the release or sealing force of the first stopper in the firstreservoir is at least 5% less than the release or sealing force of thesecond stopper in the second reservoir.
 7. The apparatus of claim 6,wherein the release or sealing force includes at least one of thefollowing forces: stiction, plunging spring force, mechanical detent,and plunger inertia.
 8. The apparatus of claim 1, wherein at least onestopper comprises a plunger that seals the outlet or the reservoir and amechanism mounted to the plunger and to the disk to maintain the plungerin the outlet.
 9. The apparatus of claim 8, wherein the mechanism is aspring.
 10. The apparatus of claim 1, wherein at least one stoppercomprises a viscous plug filling the outlet.
 11. A method for vectordispensing a fluid, comprising: providing at least one fluid in a firstreservoir and in a second reservoir on or in a disk, wherein thereservoirs are offset from a central axis of the disk, and wherein eachreservoir has an outlet, the outlet of the first reservoir facing afirst direction relative to the central axis and the outlet of thesecond reservoir facing a second direction relative to the central axis,wherein the second direction differs from the first direction; providinga stopper in the outlet of each reservoir to seal the reservoirs;spinning the disk about its central axis; and varying at least one ofinitial disk spin rate, angular acceleration of the spinning disk andduration of angular acceleration of the spinning disk to produce anacceleration force vector in the first direction to release the stopperand the fluid from the first reservoir, while the stopper in the secondreservoir continues to contain the fluid in the second reservoir. 12.The method of claim 11, further comprising, after releasing the fluidfrom the first reservoir, again varying at least one of initial diskspin rate, angular acceleration of the spinning disk and duration ofangular acceleration of the spinning disk to produce an accelerationforce vector in the second direction to release the stopper and thefluid from the second reservoir.
 13. The method of claim 11, wherein atleast one stopper comprises a plunger that seals the outlet and amechanism mounted to the plunger and to the disk to maintain the plungerin the outlet.
 14. The method of claim 11, wherein at least one stoppercomprises a viscous plug filling the outlet.
 15. A method forsequentially dispensing a fluid, comprising: providing at least onefluid in a first reservoir and in a second reservoir on or in a disk,wherein each reservoir has an outlet, wherein the first reservoir isoffset from a central axis of the disk by a first radius, wherein thesecond reservoir is offset from the central axis of the disk by a secondradius; providing a first stopper in the outlet of the first reservoirto seal the first reservoir and a second stopper in the outlet of thesecond reservoir to seal the second reservoir, wherein the firstreservoir is distinguished from the second reservoir by: a) the firstradius being greater than the second radius; or b) the first stopper inthe first reservoir having a first release force, the second stopper inthe second reservoir having a second release force, and the firstrelease force being lesser than the second release force; and spinningthe disk about its central axis at an angular velocity to generate acentrifugal force on each of the stoppers, the centrifugal force on thefirst stopper being at least as great as the first release force, andthe centrifugal force on the second stopper being less than the secondrelease force, such that fluid is released from the first reservoirwithout being released from the second reservoir.
 16. The method ofclaim 15, further comprising, after releasing the fluid from the firstreservoir, increasing the angular velocity at which the disk spun togenerate a centrifugal force on the second stopper that is greater thanthe second release force such that fluid is released from the secondreservoir.
 17. The method of claim 15, wherein at least one stoppercomprises a plunger that seals the outlet and a mechanism mounted to theplunger and to the disk to maintain the plunger in the outlet.
 18. Themethod of claim 15, wherein at least one stopper comprises a viscousplug filling the outlet.
 19. A method for sequentially regulating adispensed fluid, comprising: providing at least one fluid in a firstflow-through channel and in a second flow-through channel on or in adisk, wherein each flow-through channel has an outlet, wherein theoutlet of the first flow-through channel is offset from a central axisof the disk by a first radius, wherein the outlet of the secondflow-through channel is offset from the central axis of the disk by asecond radius; providing a first stopper including a spring and aplunger in the outlet of the first flow-through channel to seal thefirst flow-through channel and a second stopper including a spring and aplunger in the outlet of the second flow-through channel to seal thesecond flow-through channel, wherein the first flow-through channel isdistinguished from the second flow-through channel by at least one ofthe following: a) the first radius being greater than the second radius;and b) the first stopper in the first flow-through channel having afirst sealing force, the second stopper in the second reservoir having asecond sealing force, and the first sealing force being lesser than thesecond sealing force; flowing fluids through the first and secondflow-through channels; and spinning the disk about its central axis at aradial velocity to generate a centrifugal force on each of the stoppers,the centrifugal force on the first stopper being at least as great asthe first sealing force, and the centrifugal force on the second stopperbeing less than the second sealing force, such that the outlet of thefirst flow-through channel is sealed to stop the flow of fluid throughthe first flow-through channel without stopping the flow of fluid fromthe second flow-through channel.
 20. A method for spin-induced aerosolcollection, comprising: providing an aerosol-collection disk with atleast one interior inlet, at least one peripheral outlet and a passagecoupling the interior inlet with the peripheral outlet; providing aparticle collector opposite the peripheral outlet; exposing the interiorinlet to an aerosol comprising gas and particles; spinning theaerosol-collection disk to draw the aerosol into the interior inlet andto exhaust the aerosol through the peripheral outlet; and collectingparticles from the aerosol with the particle collector, where passage ofaerosol into the interior inlet, through the passage and out theperipheral outlet of the aerosol-collection disk is driven by a forceconsisting essentially of centrifugal acceleration of the aerosolgenerated by the spinning of the aerosol-collection disk.
 21. The methodof claim 20, wherein the particle collector includes at least a sectionof an annular band to which the particles adhere upon contact.
 22. Themethod of claim 20, further comprising: mounting the aerosol-collectiondisk on a rotary stage to spin the aerosol-collection disk; thenremoving the aerosol-collection disk from the rotary stage;incorporating the collected particles into a fluid; storing the fluid ina reservoir on or in a fluid-dispensing disk; mounting thefluid-dispensing disk on the rotary stage; and controlling rotation ofthe fluid-dispensing disk on the rotary stage to control dispensing ofthe fluid from the reservoir.
 23. The method of claim 20, wherein theaerosol-collection disk also serves as a fluid-dispensing disk, themethod further comprising: incorporating the collected particles into afluid; storing the fluid in a reservoir on or in the disk; andcontrolling rotation of the disk on the rotary stage to controldispensing of the fluid from the reservoir.